What is the Yellow Fever Antibodies test?

The Yellow Fever Antibodies test is a blood test that measures antibodies produced by the immune system against the yellow fever virus. These antibodies usually develop after vaccination or, less commonly, after natural infection.

The test typically detects IgG antibodies, which reflect longer-term immune memory. It is not used to diagnose acute yellow fever infection but is valuable for assessing immune protection, particularly when vaccination history is unclear or documentation is missing.

Clinically, this test is used for travel-related immunity checks, occupational screening, and selected medical assessments.

Why do I need a Yellow Fever Antibodies test?

Yellow fever vaccination provides long-lasting protection for most people, but documentation may be lost or immunity status uncertain. Some individuals may also be unable to receive the vaccine due to medical contraindications.

Testing helps confirm whether protective antibodies are present, supporting informed decisions around travel, vaccination needs, or medical exemptions.

You may need this test if you:

• Need proof of immunity for travel or work
• Are unsure whether you were vaccinated in the past
• Cannot receive the vaccine due to medical reasons
• Require confirmation of immune response after vaccination
• Work in healthcare or laboratory settings
• Are planning travel to yellow fever–endemic regions

Benefits of the Yellow Fever Antibodies test

1. Confirms immunity status
   Identifies whether protective antibodies are present.
2. Supports travel planning
   Useful when vaccination records are unavailable.
3. Avoids unnecessary revaccination
   Prevents repeat vaccination if immunity is already present.
4. Assists medical exemption decisions
   Helpful for individuals with vaccine contraindications.
5. Simple blood test
   No live vaccine or travel clinic visit required.
6. Supports occupational screening
   Relevant for healthcare or laboratory work.
7. Provides clinical reassurance
   Confirms immune memory years after vaccination.
8. UK-wide availability
   Accessible via clinic or home testing.

Step-by-step – How we offer this test

Option 1: Clinic-based blood test (UK-wide)

• Choose your nearest UK clinic
• Attend your appointment
• A clinician draws a blood sample
• Sample sent for antibody analysis

Option 2: Home or hotel visit (+£60, UK-wide)

• A qualified phlebotomist comes to your location
• Blood sample taken at home or in your hotel
• No travel required
• Identical laboratory processing and reporting

Your results explained

Negative or low antibody levels

Low or undetectable antibodies suggest no confirmed immunity to yellow fever.

Typical UK interpretation (negative/low):

• Below laboratory reference range

This may indicate the need for vaccination or further clinical advice before travel.

Positive / protective antibody levels

Detectable antibodies within the reference range indicate immunity, most commonly due to prior vaccination.

Typical UK interpretation (protective):

• Within or above laboratory reference range

This suggests adequate immune memory against yellow fever.

High antibody levels

High antibody levels usually reflect strong immune response following vaccination or past exposure.

Typical UK interpretation (high):

• Above laboratory reference range

High levels are not harmful and generally do not require action.